There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

2005년 대한 생화학·분자생물학회 하계학술대회를 다녀와서

Ebook: Qualitative data analysis , Ebook: Qualitative data analysis , کتابخانه دیجیتال جندی شاپور اهواز

Ebook: Qualitative data analysis

A solventless method was adopted to synthesize two benzoxazine monomers from naturally occurring sources, i.e., eugenol (an extraction from clove), furfurylamine, stearylamine, and paraformaldehyde. The structure of the extracted eugenol and synthesized monomers were supported by FT-IR, 1H NMR, 13C NMR, and mass spectral analysis. The monomers were polymerized/copolymerized via ring-opening polymerization by heating as shown by FT-IR (disappearance of the peak due to oxazine ring at 920 cm–1) and differential scanning colorimetry (DSC). The exothermic peak associated with curing was observed between 198–254 °C. DSC analysis shows that the onset of curing temperature for the copolymers decreased linearly from 207–202 °C on increasing the content of F-Bz. The results from TGA analysis indicate that PF-Bz shows the maximum thermal stability when compared with PS-Bz and their copolymers. In the case of the copolymers, as the F-Bz content is increased, the thermal stability also increases. All the polymers als...

Synthesis and Copolymerization of Fully Biobased Benzoxazines from Renewable Resources

Degradation and mineralization of ibuprofen (IBU) were investigated using Ultraviolet (UV) Light Emitting Diodes (LEDs) in TiO 2 photocatalysis. Samples of ultrapure water (UP) and a secondary treated effluent of a municipal wastewater treatment plant (WWTP), both spiked with IBU, as well as a highly concentrated IBU (230 mg L −1 ) pharmaceutical industry wastewater (PIWW), were tested in the TiO 2 /UV-LED system. Three operating parameters, namely, pH, catalyst load and number of LEDs were optimized. The process efficiency was evaluated in terms of IBU removal using high performance liquid chromatography (HPLC) and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS). Additionally, the mineralization was investigated by determining the dissolved organic carbon (DOC) content. The chemical structures of transformation products were proposed based on the data obtained using liquid chromatography with a high resolution mass spectrometer ion trap/time-of-flight (LC-MS-IT-TOF). A possible pathway of IBU degradation was accordingly suggested. Bioassays were performed using the marine bacterium Vibrio fischeri to evaluate the potential acute toxicity of original and treated wastewaters. TiO 2 heterogeneous photocatalysis was efficient to remove IBU from UP and from PIWW, and less efficient in treating the wastewater from the municipal WWTP. The acute toxicity decreased by ca. 40% after treatment, regardless of the studied matrix.

Heterogeneous Photocatalytic Degradation of Ibuprofen in Ultrapure Water, Municipal and Pharmaceutical Industry Wastewaters Using a TiO2/UV-LED System

Size tunable mesoporous carbon microspheres using Pluronic F127 and gelatin as co-template for removal of ibuprofen.

The research deals with the intrinsic and extrinsic motivation of EFL learners in learning English. This research used the qualitative design to find out the EFL learners’ motivation in learning English, specifically to their intrinsic and extrinsic motivation. The participants consist of 40 senior high school students in Langsa. The questionnaire was the instrument used in collecting data. The questionnaire consists of 35 items, in which they are divided into two parts. The first part, numbers 1 until 20, is to collect the information about intrinsic motivation and inquires about interest, need, hobby and goal. Meanwhile, the second part, numbers 21 until 35, is to collect information about extrinsic motivation and inquires about teachers, parents, and the environment. The results showed that the component in the extrinsic motivation that gave the biggest impact to the students are the teachers; who are the student’s biggest influence in learning English. Meanwhile, the biggest component of intrinsic motivation is the students’ own learning goals. The paper further describes each of these factors in relation to their motivation. The implication of this study related to the teachers’ efforts and capability in motivating their students to learn English is also discussed.

/pdf/efl-student-s-motivation-in-learning-english-in-langsa-aceh-2rvkofznqx.pdf

EFL student’s motivation in learning English in Langsa, Aceh

Synthesis of mesoporous carbon using gelatin as source of carbon by hard template technique (endotemplating) and its characterizations had been investigated. The mesoporous silica (SBA-15) as a template was reacted with the gelatie in a H2SO4 solution. The template-polymer composite was then pyrolyzed under a nitrogen flow at 900 °C for 3 h to carbonize the polymer and finished by silica removal from the composite using NaOH solution at temperature of 70 °C The properties of samples were characterized by N2 adsorption- desorption isotherms, transmission electron microscopy (TEM), Fourier Transformation Infra Red Spectroscopy (FTIR), energy dispersive X-ray (EDAX) and Differential Thermal Analysis-Differential Scanning Calorimetry (DTA-DSC). The results showed that the ordered mesoporous carbon was obtained after dehydration, pyrolysis and silica removal process. The presence of nitrogen atoms in the gelatin as the precursors of carbon improved the thermal stability of the carbon. The mesoporous carbon sample have high content of carbon (85 wt.%) and thermal stabliity (up to 1400 °C), specific surface areas of 580 m 2 /g, total pore volumes of 0,5 cm 3 /g, and pore diameter of 3,8 nm.

/pdf/synthesis-of-mesoporous-carbon-using-gelatin-as-source-of-50prjyaylb.pdf

Synthesis of mesoporous carbon using gelatin as source of carbon by hard template technique and its characterizations

Wormhole-like mesoporous carbon from gelatine (WMCG) with two different pore diameters have been synthesized by adopting a modified infiltration treatment. The infiltration effect on the morphology was investigated. The results show that the WMCG sample was obtained after dehydration, pyrolysis and silica removal process. The pore diameters WMCG are 15.2 and 4.8 nm with specific surface areas of 280 m 2 /g, total pore volumes of 0.5 cm 3 /g and the thermal stability up to 1400 °C. The bimodal pore of WMCG obtained as the high step of infiltration level effect.

https://www.jurnal.ugm.ac.id/ijc/article/download/21137/13842

Wormhole-Like Mesoporous Carbons from Gelatine as Multistep Infiltration Effect

https://iopscience.iop.org/article/10.1088/1742-6596/1157/4/042015/pdf

Maria Ulfa

Papers

Size tunable mesoporous carbon microspheres using Pluronic F127 and gelatin as co-template for removal of ibuprofen.

EFL student’s motivation in learning English in Langsa, Aceh

Synthesis of mesoporous carbon using gelatin as source of carbon by hard template technique and its characterizations

Wormhole-Like Mesoporous Carbons from Gelatine as Multistep Infiltration Effect

The identification and analysis of students’ misconception in chemical equilibrium using computerized two-tier multiple-choice instrument